Brainstem

Question 1

Radicular arteries feed into

Answer 1

the spinal arteries

Question 2

Cerebellar peduncles are on _____ and are not seen ____

Answer 2

each side of midline, not seen in sagittal (midline) sections

Question 3

Cerebellar peduncles connect

Answer 3

the cerebellum with other parts of

the brainstem

Question 4

Instructions to motor neurons are

carried from the brain by

Answer 4

descending tracts

Question 5

The corticospinal tracts arise in the

_______ and end in the____ (after crossing the midline).

Answer 5

Cerebral cortex, spinal cord

Question 6

Why do both motor and sensory tracts decussate?

Answer 6

Each side of the brain controls the other side of the body

Question 7

Degenerate corticospinal tracts are replaced by

Answer 7

Astrocytes

Question 8

Corticospinal and rubrospinal tract similarities

Answer 8

Both tracts are dorsal to the denticulate ligament

• > voluntary movement
• > descending

Question 9

Corticospinal and rubrospinal tract differences

Answer 9

1. Rubrospinal tract synapses at red nucleus
2. Rubrospinal has fewer axons
3. Corticospinal tract modulates sensory info

Question 10

The corticospinal tracts arise from

Answer 10

neurons in the cerebral cortex and pass down the brainstem near its ventral surface

Question 11

Corticopontine fibres

Answer 11

information from cerebral cortex via pons to cerebellum

Question 12

The basilar artery supplies

Answer 12

the pons

Question 13

Locked in syndrome occurs when

Answer 13

a branch of the basilar artery supplying the

corticospinal tracts is blocked

Question 14

In the open medulla what structure is noted

Answer 14

Olives

Question 15

In a section of closed medulla we see

Answer 15

Central canal and pyramids

Question 16

How do Primary afferent fibres in peripheral
nerves carry sensory information to the
spinal cord ?

Answer 16

Through dorsal root

Question 17

Dorsal root ganglion contains cell bodies of

Answer 17

sensory neurons

Question 18

1a fibre function

Answer 18

Monitors muscle stretch speed changes

Question 19

C fibre function

Answer 19

pain

Question 20

Abeta function

Answer 20

position

Question 21

General pattern of somatosensory tracts

Answer 21

1. Primary sensory neurones
2. Second order neurones on same side of CNS
   - > cross midline
3. Neurons in thalamus send signals to somatosensoy cortex

Question 22

Two important somatosensory pathways in the spinal cord are? and their functions?

Answer 22

1. Spinothalamic tract: nociception(pain); temperature; touch
2. Dorsal column/ medial lemniscus system: two point discrimination; conscious prioprioception; vibration sense

Question 23

Outline spinothalamic tract pathway

Answer 23

1. Starts cerebral cortex
2. Synapse in thalamus
3. Axon in spinothalamic tract
4. Synapse in superficial dorsal horn of SC
5. Primary afferent to skin/muscle

Question 24

Outline dorsal column/ medial lemniscus system pathway

Answer 24

1. Starts cerebral cortex
2. Synapse in thalamus
3. Axon in medial lemniscus
4. Synapse in medulla -> second order neuron in dorsal column nucleus
5. Axon in dorsal column until large primary afferent in drg reaches skin

Question 25

Lumbar cord gives rise to

Answer 25

lumbar spinal nerves mainly for lower limbs

Question 26

c fibres (nociceptive) end in

Answer 26

the superficial dorsal horn

Question 27

Second order neurons have axons that cross the midline to

Answer 27

join the spinothalamic tracts

Question 28

Fasciculus gracilis carries information from what part of the body?

Answer 28

from the middle thoracic and lower limbs of the body

Question 29

Where are the lower limb fibres in the medial lemniscus?

Answer 29

lateral mid-pons/ mid brain

Question 30

Which structure in the midbrain has descending control over pain?

Answer 30

Periaqueductal grey